JPH0114490B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating device capable of detecting the weight of an object to be heated.

Generally, in the case of a high frequency heating device, the heating time is determined by the weight of the object to be heated. In addition, for heating devices such as electric ovens equipped with electric heaters,
When preparing ingredients, it is important to accurately measure the weight of each ingredient and carefully mix them.

As described above, for heating devices, it is very important to measure the weight of the object to be heated. Therefore, many devices have been devised to date that incorporate a scale as a part of the heating device or in the heating chamber.

Based on these backgrounds, the present invention embodies a heating device that is easier to use and has a safer weighing function. The configuration of the present invention will be explained below with reference to the drawings.

FIG. 1 is a perspective view of the main body showing the appearance of the heating device according to the present invention, and FIG. 2 is a detailed view of the main part of the operation panel.

In both figures, a door body 2 which is pivotally supported so as to be openable and closable, and an operation panel 3 are disposed on the front surface of the main body 1. On the operation panel 3, there are provided a display section 4, a timer knob 5 for inputting the heating time to the control section, a temperature knob 6 for inputting the heating temperature, and various function keys 7.

FIG. 3 is a sectional view of the heating chamber. A magnetron 9 serving as heating means is coupled to the heating chamber 8 and irradiates the heating chamber 8 with microwaves. A mounting plate 10 is installed in the heating chamber 8, and a receiving plate 11 is placed on top of the mounting plate 10 on which the sliding piece 1 is placed.
It is detachably attached to 2. The sliding piece 12 extends outside the heating chamber, and one end of the sliding piece 12 is connected to a plate spring 13 serving as a support part.
Supported by A strain gauge 14 serving as a load sensor is fixed to the leaf spring 13 to measure the weight of the object to be heated 15 and input it to the control section 16 . The control unit 16 controls the power supply to the magnetron 9 based on this data to perform optimal heating.

The saucer 11 is molded from plastic such as polypropylene with low dielectric loss, and has a large number of through holes 17 to allow drips of the object to be heated 15 to fall downward and to reduce the weight of the saucer itself.

The strain gauge 14, which is a load sensor, has the shape of a resistance foil 19 printed on a base 18, as shown in FIG. This resistance foil 19
By utilizing the fact that the resistance value changes due to expansion and contraction, the strain of the leaf spring 13, that is, the heated object 15
Measure the weight of. 20 is a protective sheet such as a laminate film. This strain gauge is fixed to the back surface of the leaf spring 13 with adhesive.

The mechanical configuration is as described above. Next, the configuration of the control section will be explained using the system block diagram shown in FIG.

The control unit includes a controller 21 composed of a microcomputer, etc., and receives user commands input from a keyboard (function key 7 on the operation panel, etc.) 22 and input from a load sensor 13 via an A/D converter 23. Based on the weight data of the object to be heated, the power supply to the magnetron 9 and the output of display data to the display section 4 are controlled via the driver 24.

With this configuration, the controller 21 can control the saucer 1
1 is in a mounted state or a detached state (that is, an unloaded state). When the wearing state is detected, a "g" display appears on the display section 4 (see FIG. 2) to notify that the control section has switched to the weight mode. In this mode, the controller 21 displays the weight of the object to be heated that has been measured thereafter. When the heating menu is selected by pressing the function key 7, the heating time and heating output are calculated and the display is switched to these. It is also conceivable that the switching point is at the start of heating or after a certain period of time has elapsed after placing the object to be heated.

On the other hand, if the tray is detected to be detached (i.e. no load condition for the load sensor), the controller changes from this weight mode to the normal heating time or heating temperature, and even the time (if it has a clock function).
etc. will be displayed again.

Now, since the sliding piece 12 is provided to protrude from the mounting plate 10 (Fig. 3), it is possible to accurately measure the object to be heated not only in the weight mode but also in the heating time or heating temperature mode. Although weight cannot be measured, its presence or absence can be detected. Therefore, heating without an object to be heated, that is, dry firing can be prohibited. This is useful because it does not impair the life of the magnetron 9 and prevents excessive leakage of radio waves.

Furthermore, in the case of electric ovens, it is possible to distinguish between preheating (dry baking) and main heating (baking of the heated object) by detecting whether or not the heated object is placed. It becomes possible to issue a notification that alerts the user so that the heating can be done without any problems. Although this embodiment has been described with respect to the stirrer method, it goes without saying that it is also applicable to a turntable method.

Now, an example in which a scale is provided in the heating chamber has been described above. However, the present invention can also be applied to an apparatus in which a scale is provided in any part of the apparatus outside the heating chamber.
For example, in a retractable scale as disclosed in Japanese Patent Application Laid-Open No. 56-7023, a switch is provided that turns on when the scale is pulled out, and this detection means turns on the control unit when a tray is installed. mode. Although this embodiment does not have the dry firing detection function as in the previous embodiment, the modes of weight measurement and time-controlled heating are automatically switched, making it easy to use and reducing the possibility of misuse.

As described above, according to the present invention, since the tray is configured to be detachable, it can be removed when not measuring weight and does not get in the way. Since the time display can be switched to the weight display, there is no need to perform operations such as pressing keys on the operation panel, for example.
Furthermore, a single display section can be used to display both weight and time/time such as heating time, making it possible to realize a resource-saving and low-cost device.

In addition, the heavy mounting plate is fixed to the bottom of the heating chamber, so its own weight is not applied to the load sensor, and the receiving plate has a through hole, so its own weight is light, allowing it to accurately measure the weight of small objects to be heated. can. Furthermore, by attaching a saucer, at least the weight of the saucer is applied to the load sensor, making it possible to reliably switch to weight display and detecting the weight of even a very small amount.

[Brief explanation of drawings]

Fig. 1 is an external perspective view of a heating device showing an embodiment of the present invention, Fig. 2 is a detailed view of the main parts of the operation panel, Fig. 3 is a cross section of the heating chamber, Fig. 4 is a strain gauge as a load sensor, FIG. 5 is a block diagram of the control section. 4...Display part, 8...Heating chamber, 9...Heating means (magnetron), 11...Saucer, 13...Support part (plate spring), 14...Load sensor (strain gauge), 15...Target Heated object, 16...control unit.

Claims (1)

[Claims] 1. A heating chamber for accommodating an object to be heated, a heating means coupled to the heating chamber, a removably configured saucer with a through hole on which the object to be heated is placed, and a heating device located below the tray for heating. A mounting plate fixed to the bottom surface of the chamber to receive juice dripping from the object to be heated, a movable piece penetrating the mounting plate, engaging with the saucer and extending out of the heating chamber, and supporting the movable piece. It consists of a load sensor that detects the weight of the object to be heated on the saucer, a control section that detects the weight of the object to be heated using this load sensor, and a display section that displays heating time, weight, etc., and the control section is The display section usually displays the heating time, etc.
The heating device is configured to determine that the saucer is attached when it is detected that a weight is applied to the load sensor, and to switch display contents to display the weight.